Atherosclerosis and Coronary Artery Disease

Atherosclerosis -- sometimes called hardening of the arteries -- can also slowly narrow the arteries throughout your body.

When atherosclerosis affects the ones of the heart, it’s called coronary artery disease. That’s the No. 1 killer of Americans. Most of those deaths are from heart attacks caused by blood clots.

Atherosclerosis can create life-threatening blockages -- without you ever feeling a thing. Since we’re all at risk for coronary artery disease, it’s worth learning more about atherosclerosis.

Cold Facts About Hard Arteries

  • More than 15,800,000 Americans have known coronary artery disease.
  • About 8 million of them have had heart attacks.
  • Around 500,000 people will die of coronary artery disease this year. More than a million will have a heart attack.
  • A third of all deaths of Americans older than 35 are due to coronary artery disease.
  • After age 40, about 50% of men and one-third of women can expect to have coronary artery disease.
  • Millions more people have severe atherosclerosis with no symptoms.
  • More men than women die from coronary artery disease. The rates for women go up after menopause, but they never catch up with men's.
  • Heart disease is the No. 1 killer in women, just as in men.


Many of us have heard that clogged arteries lead to heart attacks. But how does atherosclerosis cause coronary artery disease?

First, the coronary arteries’ smooth interior surface is damaged. High blood pressure, abnormal cholesterol levels, cigarette smoking, and diabetes are the most common reasons why.

LDL -- or "bad" cholesterol -- then starts to build up in the coronary artery’s wall. The body sends a "clean-up crew" of white blood cells and other cells to the toxic site.

Over years, continuing buildup of cholesterol and the body’s response to it create a plaque. That’s a bump on the artery wall that can obstruct blood flow.

Plaques’ Sneak Attacks

Atherosclerosis plaques in the coronary arteries can behave in several ways:

They can grow slowly, never blocking the artery or causing clots.

They can expand and block blood flow in a coronary artery. This may cause no symptoms, even when the artery is very blocked.


Other times, a blockage does cause symptoms. Called “stable angina,” this is most common chest pain with activity. It goes away with rest. It’s not a heart attack.

A plaque can rupture. The material inside the plaque goes into the bloodstream. That causes blood to clot quickly inside the coronary artery.

A plaque rupture is as terrible as it sounds. The result is a blood clot that makes your chest hurt.

Two things can happen then:

Unstable angina: The clot doesn't totally block the blood vessel. It then dissolves without causing a heart attack.

Heart attack (myocardial infarction): The coronary artery is blocked by the clot. Heart muscle, starved for nutrients and oxygen, dies.

Blood clots commonly occur in arteries with minor blockages. Fewer than one in five people who have a heart attack have had angina for a while before.

And for as many as 50% of men, the first symptom of atherosclerosis is sudden death from a massive heart attack.

Reduce Your Risk of Coronary Artery Disease

No one can predict who will have a heart attack. But coronary artery disease isn’t random. Most people with coronary artery disease have one or more controllable risk factors.

Studies say upwards of 80% of the chance of a first heart attack is determined by the factors below. These generally cause atherosclerosis. They are also the causes of coronary artery disease:

Most of us have plenty of room for improvement.

The best way to determine your risk level is to see your doctor. But you can start to reduce your risk today. Eat right, don’t smoke, and exercise.

Some people may also need to take medicine to keep their cholesterol and blood pressure under control.

WebMD Medical Reference Reviewed by James Beckerman, MD, FACC on September 14, 2016



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Mark Silverman, MD, emeritus professor of medicine, Emory University School of Medicine, chief of cardiology, Piedmont Hospital, Atlanta.

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